10
Electrical
news
Warning issued
about non-compliant
switchboards
ESV has issued a safety alert
about the dangers of gaps
in switchboard enclosures
following a recent incident
involving a large arc event.
By Vanessa Garbett, Compliance Officer
There has been a recent serious incident
involving a large arc event caused by
material falling through an opening in a
switchboard enclosure. The switchboard
enclosure did not comply with the relevant
Australian Standards, in particular AS/NZS
3000:2007 and AS/NZS 3439.1:2002.
On investigating this incident, it has become
a matter of concern to ESV that there appears
to be confusion in the industry as to the IP rating
requirements of switchboards and a lack of
understanding of the responsibility for compliance.
It is also of concern to ESV that the potential
for incorrect switchboard design, construction and
installation, and subsequent electrical incidents, is
not being recognised within the broader industry.
Lug falls through gap
The incident involved two electrical workers
who were working in a switchboard enclosure,
forming part of a large switchboard, fitting a
lug to the end of a cable. Lock out, tag out
procedures were used and in place. A tinned
copper lug fell through a 23mm gap at the rear of
the switchboard enclosure. The lug fell onto a live
electrical busbar enclosure that was below the
switchboard enclosure being worked on. The lug
came into contact with the live busbars causing
a short circuit and subsequent arc event that
resulted in extensive switchboard damage.
The 23mm gap at the rear of the switchboard
enclosure is non-compliant, was not obvious and
was not picked up by the:
»» switchboard designer
»» switchboard supplier
»» switchboard builder
»» switchboard installer
»» registered electrical contractor
»» licensed electrical workers or
»» licensed electrical inspector.
This particular type of switchboard is a
modular system. The switchboard manufacturer
type tests the modular switchboard system.
Compliance is then achieved by the
manufacturer’s instructions being followed by the
switchboard suppliers, builders and installers.
In most cases with modular systems, the
design of the required switchboard is submitted
to the switchboard supplier to generate the
required parts. The switchboard is then built to the
manufacturer’s instructions (manual). Switchboard
compliance is reliant on the initial design along
with the construction and installation.
The onus of ensuring compliance of the
switchboard, when installed, lies with (but may
not be limited to) the LEW, REC and LEI, who
carried out the work and signed off on the relevant
Certificate of Electrical Safety.
In this instance the design, construction and
installation of the switchboard failed to meet the
requirement of the IP2X rating from one enclosure
to another.
Avoid the gap: Electrical workers need to be
aware of the dangers posed by non-compliant
switchboards. Two electrical workers were lucky
they weren’t injured when a lug fell through a
23mm gap in the back of a switchboard and fell
on to a live electrical busbar.